POS1214 COVID-19 VACCINATION RATE AND SAFETY PROFILE IN PATIENTS AFFECTED BY MIXED CRYOGLOBULINEMIC VASCULITIS.
Authors: C. Vacchi, S. Testoni, M. Visentini, R. Zani, G. Lauletta, L. Gragnani, D. A. Filippini, C. Mazzaro, P. Fraticelli, L. Quartuccio, R. Padoan, L. Castelnovo, A. L. Zignego, C. Ferri, A. Hoxha, C. Salvarani, G. Monti, M. Galli, M. Sebastiani
Journal: Annals of the Rheumatic Diseases (2022)

Background Mixed cryoglobulinaemic vasculitis (MCV) is an immune-complex-mediated systemic vasculitis characterized by heterogeneous clinical manifestations mainly involving skin, kidney and peripheral nervous system. Despite reassuring safety data from EULAR Coronavirus Vaccine (COVAX) physician-reported registry, a significant proportion of patients with autoimmune diseases reported unwillingness to get vaccinated against SARS-CoV-2 infection in the preliminary results of the COVAD study, due to concerns about the lack of long-term safety data, and fear of associated side effects and disease flare. Objectives Aims of this multicentre Italian study were to investigate the prevalence of vaccination against SARS-CoV-2 in Italian population of MCV patients, to explore the reason for the missed vaccination, and to investigate short and long-term side effects of the vaccine, including vasculitis flare. Methods All MCV patients referring to 12 Italian centres were investigated about vaccination and possible both short- (within 48 hours) and long-term (within 30 days) adverse events (AE), classified according to FDA Toxicity Grading Scale for preventive vaccine clinical trials, and possible disease flares. Patients with MCV related to lymphoproliferative disorders or connective tissue diseases were excluded from the study. The baseline variables were expressed as percentages or mean±standard deviation. The differences between continuous variables were analysed using the Mann–Whitney nonparametric test. The chi-squared test, or Fischer’s exact when appropriate, were used for categorical variables (absolute numbers and percentages) regarding baseline characteristics. Results A total of 416 patients, 69.2% females and 30.8% males, with a mean age of 70.4±11.7 years, were included in the study. Only 7.7% of patients were not vaccinated, mainly for fear of adverse events (50%) or for medical decision (18.8%). Corminaty was the vaccine most frequently used (80.5%). Interestingly, 6 patients (1.44%) were with a heterologous vaccination (usually AstraZeneca-Corminaty). Considering ongoing treatment, not vaccinated subjects were more frequently treated with chronic glucocorticoid therapy and/or Rituximab (p=0.049 and p=0.043 respectively). AE were recorded in 31.7% of cases, mainly mild and self-limiting (grade 1). More severe adverse events, such as flare of vasculitis, were observed in 5.3% of cases. AE were not associated with the kind of vaccine used and with the clinical manifestations of vasculitis. Patients with active MCV showed a lower frequency of short-term (within 48 hours) adverse events, but patients affected by peripheral neuropathies or skin vasculitis frequently showed a flare of their symptoms, recorded in 40% and 25% of cases, respectively. Finally, patients under glucocorticoid treatment were more prone to develop a vasculitis flare within a month after vaccination. Conclusion Vaccination in MCV patients has been performed in a high percentage of patients showing a good safety. Other than patients’ fear, treatments with rituximab and glucocorticoids are the main reasons for delaying vaccination, and it should be considered by the physician before starting therapy. Vasculitis flares were observed in about 5% of cases, in line with that observed in other autoimmune diseases. Specific attention should be reserved to people with purpura or peripheral neuropathy, for the increased risk of exacerbation of their symptoms. References [1]Visentini M et al Flares of mixed cryoglobulinaemia vasculitis after vaccination against SARS-CoV-2 2021 [2]Machado PM et al Safety of vaccination against SARS-CoV-2 in people with rheumatic and musculoskeletal diseases: results from the EULAR Coronavirus Vaccine COVAX physician-reported registry 2021 [3]Sen P et al COVAD Study Group. COVID-19 vaccination in autoimmune disease COVAD survey protocol 2022 [4]Scarpato S et al Italian Group for the Study of Cryoglobulinaemia GISC. Provisional recommendations for SARS-CoV-2 vaccination in patients with cryoglobulinaemic vasculitis 2021 Disclosure of Interests None declared